the necessary suction at the suction port and inthe main suction line to the distributor valves fordeflating the deice boots.SUCTION RELIEF VALVE. The suctionrelief valve installed in the suction manifold linesleading from the ejector to the tail sectiondistributor valve regulates deice system suction.When suction in the manifold lines becomesexcessive, the spring tension that seats the reliefvalve is overcome, and the valve opens to permitcompartment air into the suction manifoldlines until the suction pressure is reduced toapproximately 6 in. Hg.An adjusting nut on the relief valve is usedto adjust the tension on the spring that seats therelief valve. On aircraft adjustment is generallyprohibited.DEICE BOOTS. The rubber deice boots(fig. 1-7) are attached to the leading edge surfaceswith cement or fairing strips and screws, or acombination of both. On the E-2A, they arebonded to the leading edges with cement andtapered slightly to provide a smooth airflow overthe boot and wing, when the boots are deflated.PRESSURE GAGE. The deice systemcockpit-mounted pressure gage indicates thepressure available for inflating the deice bootswhen the system is operating. The gage iscalibrated from 0 to 20 psi in 1 psi increments.Normal system operation is indicated by a slightpressure fluctuation of the pointer. This fluctua-tion is caused by a momentary drop in pressureat the beginning of each inflation period for eachdeice boot group. A steady reading of 18 psi onthe gage indicates a nonoperating condition.SUCTION GAGE. The deice system cock-pit-mounted suction gage indicates the suctionavailable for deflating the deice boots. The 0 to10 in. Hg gage is calibrated in major incrementsof 1 in. Hg and minor increments of 0.2 in. Hg.Slight pointer fluctuation indicates proper systemoperation, as was the case with the pressure gage.A steady reading of 6 in. Hg on the gage indicatesa nonoperating condition.Deice Boot System MaintenanceMaintenance of deice boot systems is normallyperformed by personnel of the AE, AME,and AMS ratings. Personnel of the AMSrating are primarily concerned with the removal,installation, and miscellaneous repairs of the deiceboots. AE personnel are concerned with removal,replacement, and repair of deice system electricalcomponents. The AME is generally responsiblefor all other components of the deice system.AME personnel assigned to the organizationallevel of maintenance are responsible for removaland replacement of malfunctioning components,maintenance of associated plumbing, and render-ing of assistance to senior personnel in theperformance of operational checkouts andtroubleshooting.Some steps of the operational check, as out-lined in the applicable MIM, are performedusing external electrical power and an external airsupply. The air supply is connected to the bleed-air line test connection and must be capable ofsupplying a pressure of 50 to 90 psi. Remainingsteps of the operational checkout require that oneof the aircrafts engines be started.NOTE: Personnel turning up naval aircraftmust be fully qualified, designated in writing, andcarry a current turnup card in accordance withOPNAV 4790.2.All steps of the operational checkout must beperformed in the sequence outlined in the MIM.When a malfunction occurs during a step, it mustbe corrected before proceeding to the next step.Troubleshooting, removal and replacement ofcomponents, and the operational checkout shouldalways be accomplished in accordance with thespecific instructions provided in the applicableMIM with appropriate emphasis on qualityworkmanship and inspection.DEICE AND ANTI-ICING SYSTEMSFOR THE S-3 AIRCRAFTThe S-3 aircraft ice protection systemprovides deicing of wing leading edge flaps andhorizontal stabilizer leading edges and anti-icingof the air-conditioning ram air inlet, enginenacelle, and parts of the engine. The bleed airtemperature control anticipator and thermostat,the deice temperature control regulator valve, andthe engine anti-icing valve interface with the iceprotection system.The deice function of the ice protection systemremoves ice that forms on the leading edges ofthe wing and horizontal stabilizer. The vertical.stabilizer leading edge is not deiced. Bleed air fromthe engine compressors 10th stage is the basicsource of heat. One requirement of the bleed-air1-11